PTEN and diffuse large B-cell lymphoma: In terms of detection level, The vast majority of reports available related to the loss of PTEN in DLBCL, in which PTEN deficiency was commonly determined using immunohistochemistry [13, 17, 18] or western-blot [8] on protein level, which was distinctively different from our current study where PTEN deficiency was evaluated using FISH method on DNA level.